Potassium (K+) is one of the most abundant intracellular cations. Potassium homeostasis is maintained predominantly through the regulation of renal excretion. Various medical conditions, such as decreased renal function, genitourinary disease, cancer, severe diabetes mellitus, congestive heart failure and/or the treatment of these conditions can lead to or predispose patients to hyperkalemia. Hyperkalemia can be treated with various cation exchange polymers including polyfluoroacrylic acid (polyFAA) as disclosed in WO 2005/097081, WO2010/022381, WO2010/022382, and WO2010/022383, each of which is incorporated herein in their entirety by reference.
In the previous methods of manufacturing, batch or semi-continuous processes were used. However, such processes are not suited to commercial production of this polymer due to increased costs, and it was accordingly an object of the present invention to find a process for the preparation of cross-linked (2-fluoroacrylate)-divinylbenzene-1,7-octadiene polymer particles, which is suitable for a production process on the industrial scale. The aim was in particular industrial processes for the preparation of crude particles (crosslinkage), their washing, drying, preparation of salts, and the consistent coordination of these processes with one another in order finally to arrive at a preparation process which is as simple and efficient as possible guaranteeing the quality requirements (formation of by-products which is as low as possible) and high yield.